[AZ-Observing] Re: February 2010 Report from Hovater Norte
- From: Tom Polakis <tpolakis@xxxxxxx>
- To: az-observing@xxxxxxxxxxxxx
- Date: Mon, 15 Feb 2010 18:05:12 -0500
---- L Knauth <Knauth@xxxxxxx> wrote:
> BTW: I always have trouble "blinking" with the OIII filter. Too much
> ambient light reflecting off the glass surface. Is there any trick other
> than using a dark cloth? I get a little uncomfortable scrunching a dark
> cloth over my head with one hand while flipping an OIII filter with the
> other, all while twisted to the side and 4 feet up a ladder.
As you say, the reflection off the filter prevents the blinking method from
working, even at the darkest sites. If your dark cloth is large enough,
though, it should stay put without having to hold onto it. Another, more
desirable option is a shield around your focuser, like this one that Chuck
Dethloff in Oregon constructed.
http://www.bbastrodesigns.com/osp01/chuck-shield.jpg
You can see that the semi-circular shield rotates to block out the light from
the sky or horizon. It stands about 6 inches out from the scope, so your head
is pretty much immersed into an area that is nearly free of extraneous light.
Tom
> Of which speaking, there are apocryphal tales that enhanced oxygen gives
> noticeably improved sensitivity to deep sky objects. Anyone ever try renting
> medical oxygen and sniffing while going for the faint photons? I've thought
> of trying it, but I would feel pretty stupid if it's just one of those lies
> we tell while standing around telescopes in the dark.
>
> Any suggestions?
>
> Paul
>
> > -----Original Message-----
> > From: az-observing-bounce@xxxxxxxxxxxxx [mailto:az-observing-
> > bounce@xxxxxxxxxxxxx] On Behalf Of Tom Polakis
> > Sent: Monday, February 15, 2010 2:32 PM
> > To: az-observing@xxxxxxxxxxxxx
> > Subject: [AZ-Observing] Re: February 2010 Report from Hovater Norte
> >
> > ---- L Knauth <Knauth@xxxxxxx> wrote:
> >
> > > Then there was NGC 2366, an asymmetric lump with a stellar
> > nucleus (?) near one edge, all next to a fan-shaped wisp. Very bright
> > for such a small object. What is going on in this system?
> >
> >
> > Paul,
> >
> > NGC 2366 is a dwarf irregular galaxy in the M81 Group, so it's pretty
> > nearby (10M light years or so). The brightening on south end is an HII
> > region with its own designation, NGC 2363. Next time you look at it,
> > "blink" it with a nebula filter, and it will really jump out, while the
> > galaxy nearly disappears from view. Using a 13" scope, I described NGC
> > 2363 as being 10" x 5", and oriented at nearly a right angle to the
> > parent galaxy. These notes were taken on a night that I rated
> > something out of 10 for transparency and something else out of 10 for
> > seeing.
> >
> > Tom
> >
> >
> >
> >
> >
> > --
> > See message header for info on list archives or unsubscribing, and
> > please
> > send personal replies to the author, not the list.
>
> --
> See message header for info on list archives or unsubscribing, and please
> send personal replies to the author, not the list.
>
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